Tapping machine



2 SHEETSSHEET 1 9 INVENTOR. Sf'eve hCS/CS S. CSENCSICS TAPPING MACHINE Sept. 2, 1952 Filed July 19, 1948 .w m m MU m mm 2 0 8 w m w 2 RF F i S CSENCSICS TAPPING MACHINE Sept. 2, 1952 Filed July 19, 1948 Patented Sept. 2, 1952 2,608,699 g TAPPING MACHINE. v Steve Csencsics, Erie, Pa. Application Jiily '19, 1948, SerialfNo.39,531

This invention relates generally to machines having a spindle adapted to reverse :its rotation upon .a predetermined longitudinal movement thereof and more particularly to machines for forming screw threadssuch as a tapping ma- "chine.

.Tapping machines for forming threads 'now on the market provide comparatively rough threads and the means of reversing the spindle of "the machine is unsatisfactory. Many of these tappin devices only provide for a small area of the disk in frictional contact with the driving members thereby making slipping thereof a frequent occurrence and only very light workccan :be performed on such a machine. In other instances, it is necessarylto pull theileverof a machine to manually move the spindle and clutch .mem-ber thereon upwardly and downwardly into engagement with the opposing, oppositely rotating, driving members. There is :a high inertia of parts in these prior machines which causes :snapping of taps and dies. Many :of these machines require the movement of the table under the spindle for operation. Other require .lugs and stops which cause a-violent engagement between rotating members therebymaking them insensitive and causing breakage and damage of taps and uneven threads. All of these prior devices require a skillful operator to form' a passable thread. These prior devices .are" insensitive,

complicated, andicostly.

It is accordingly an object of my invention to provide a machine having a spindle'ad'apted for reversible operation which overcomes the above and other defects in such machines and it is more particularly an object of my invention'to'provide such a machine which is simple in construction, economical'in cost, economical in manufacture, andeflicient and simple in operation.

Another object of my invention is to provide 'a machine having a reversible'spindle which has a low inertia constant to prevent tool breakage.

Another object of my invention is to provide a machine with a reversible spindlewhich is extremely sensitive to the application of pressure. Another objectlof my.;inve1 1tion'isto provide a machine with a reversible-spindle wherein the reversing movement is faster than. the drivingmovement to quickly remove a'tap or die;

Another-object of my invention is toprovide a machine-having :a reversible spindle which automatically reverses itself upon a, predetermined movement of the spindle after engagement of a tap or die with the work piece. a l 1 Another object of-my invention is to provide iclaim. (Chili-r136) ""irii a machine having a reversible :spindle vwhich eliminates all lugsan'd stops and, other devices causing-violent impactaction; r

-.-Another object of my invention is toprovidem "machinerhaving 'a reversible spindle which very gradually overcomes the inertia of the (spindle uponistarting and reversing.

Another objector my inventionis to provide -a machine for cuttin threads which automatically rotates the spindle and thread "cuttinggmembe'r movable therewith 1111 a clockwise direction-upon engagement of the thread cutting member with a work piece and which automaticallyreverses the spindle upon-apredetermined longitudinal movement of the thread cutting'm-ember into, the workpiece. f Other-objects of my invention will become :evident from the following detailed description, *takenlin conjunction. with the accompanying drawings, in which Fig. -1 is a side elevational viewwwith thereof broken away or my-novelrmachinesfer cutting screw threads; Fig. 2 is a plan view of my 'novelrmachine; for 'cuttingscrew threads; 1 Edi Fig 3 is a side elevationalviewcfmy-novel machine for cutting screwth-readsy'and r Fig. 4 is a view takenonthe'line :of .Fig; l. Referring now to-the drawings, I showin-Figt. 1, 2, 3 and 4, a vertically extending,hollow,cy1indrical support member l which may-besupported on 3 any suitable lbase mounted on 11a Ifioor or v a bench. n' 'movable work. table (notrshownhis supported on the lower end of the support meme her 1. A head frame 2 has an aperture itformed on one end thereof for engagementwith'the hol low support member I. A longitudinalslittis formed in the frame 21 to permit the .apertured portion 3 thereofto slide overthe support meme her I. :Bol-t and nut assemblies 5.:eXtendrtransiversely of the slit .portion'4 of therframezl-tmsee cure it in any predetermined vertical po'sitionrdn the support member'i. The frame2 has-a trans: versely extending apertured cylindricalrporition :6-1to journal a shaft] which has .amuIIeyL -I mounted on ;one.end thereof. jAn adjustableiarm 9 is secured tothe-oppositeisideofitheitransverse portion-6 and it has a shaftilll extendingthrmzzh one end thereof for mountingka 'pulle stepped pulley 13is also mountedonithe shaft :HI and it is opposedby a diivi'n'g s'tepped pulley on shaft 1 5 which is driven by fa' suitable iec tricjmotor It. The electricmotor I liismounted on the support member 1 byan: an-apertlired supportbra'cktl land ina chine bolts 1!. A belt 3 I9 is trained over the pulleys |3 and I4 to transfer rotatlve force therebetween.

The frame 2 has spaced, laterally extending apertured arms 2|, 22, and 23, forming recessed portions 24 and 25. The recessed portion 24 has nested therein a driving disk 26 and an opposed driving disk 21 smaller in diameter. Pulleys 2B and 29 are formed integral with the disks 26 and 21 and an endless belt 21a is trained over the pulley 8, the pulleys '28 and 29, and the pulley 12 thereby causing the disk 26 tomove' in a direction reverse of that of the disk 21. ing arms 2|, 22, and 23 have alined apertures 33;

34, and 35 therein. A flanged bushin 36"is'dis- 1 posed in the aperture 33 in the arm 2| and it is held in place by a lock screw 31. A thrust bear-'- The projecting 38 is disposed adjacent the flange 39 on the bushing 36 and it is also disposed in the recessed portion 40 of the disk member 26 thereby permitting the disk member 26 to rotate freely on the flanged portion 39 of the bushing 36. A hollowspindle 42 extend through the bushing 36 and through the aperture 34 in the arm 22. 'A

:double faced disk unit or clutch 43 is spaced from and disposed between the disk members 26 and :21 and it is fixed against rotation on the spindle 4-2 by a locking screw 43a. The disk member 21 ,-is mounted on a bearing member 44 which is nested in a central recess 45 thereof and it engages the upper face of the arm 22.

wardly extending flange 46 on the lower end The spindle 42 and the 'doublefaced clutch member 43 are movable longitudinally s0 that the clutch member 43 mayengage either of the disk members 26 or 21 alternately. The spindle 42 has an outthereof and it engages the inwardly projecting flanged portion 41 of a cup shaped member 48 with a ring washer 49 disposed therebetween. :The cup shaped member 41 has an inner threaded portion '50 for threadably engaging the reduced threaded end 52 of a stationary cylindrical member 53, the lower end of which is journalledin the aperture in the arm 23. l A sleeve 54' is 53 and it has rack teeth 55 formed on one side thereof for engagement with a gear 56 mounted on a transverse shaft 51. Also mounted on the transverse shaft 51 is a rectangular block member -58- which is secured in a cut out portion 59 of member 64 for receiving a tap or any other cutting tool. The shaft 63 has an annular flange 6|." formed on the lower end thereof on which is disposed a bearing assembly'92 and the sleeve 54., It will be evident that a' chuck for holding a die may be utilized in'steadof the chuck 64 without departing from my invention. The

upper end of the shaft 63 has a keyway 65 for engaging a key 66 which in turn engages a keyway':61 in the upper end of the sleeve 42 so that the shaft 63 and the sleeve42 rotate together but may movelongitudinally relative to each other.

A flanged collar 68 is disposed around the upper end of the sleeve 42 and it is spaced from the telescopically disposed in the cylindrical member W upper face of thearm .2l by a coil spring '69. A

trally thereof at 90 by an adjustable threaded bracket 18 and a transversely extending pin 13.

i A counterweight is hung on the grooved por- "tion 8| of the outer end of the arm 11. The

counterweight 80 urges the sleeve 54 upwardly to aneutral position in the cylindrical member 53. An annular stop member 82 is secured to the upper end of the shaft 63 by a lock nut 83 to adjustably limit the longitudinal movement of the shaft 63 and to cause the rotating spindle 42 and clutch member 43 to move downwardly therewith into engagement with thedriving disk 21 thereby reversing the rotation of the spindle 42 and the shaft 63,'when the taper screw cuttin member has moved longitudinally a predetermined amount.

In the operation of my machine, the double faced disk clutch 43 normally rides between the driving disks 26 and 21 and is sensitively balanced therebetween by the spring 69. In this neutral position, the spindle 42 and the shaft 63 remain at rest. Likewise, the counterweight 80 causes a sensitive balance of the sleeve 54in the cylindrical member 53. Upon rotation of the handle I16, the shaft 51 and gear 56 thereon is rotated causing a downward movement of the sleeve 54 and the shaft 63 against the force of the counterweight 86. The shaft 63 and the sleeve 54 move downwardly until a tap or die (not shown) in the chuck 64 engage the-work piece upon which a thread is to be formed When the downward movement of the shaft 63 is stopped by the. engagement of the tap with a work piece, the gear 56 moves upwardly'onthe rack teeth 55 of. the sleeve 54 whereby the block member .58 being secured to cylindrical member 56 causes the cylindrical'member 53' and the rotatable-spindle 42 to move upwardly. The upper face of the double faced'clutch 43 then engages the-driving disk 26, which normally ro tates in a clockwise direction, thereby rotating the spindle 42 and shaft 63 in a direction to cut the thread. Upon further rotation of the handle I10, the tap moves into the workpiece to cut the thread. The sleeve 54. and shaft 63 move'longitudinally upon further rotation of the gear 56 after the clutch 43 and the driving disk 26 have been engaged. When the shaft 63 has moved downwardly a predetermined amount; the stop collar 82 engages theupper end of the spindle 42 to move itand the clutch 43 downwardly. This causes the lower face of the clutch member '43 to move downwardly into engagement with the reversing driving disk 21 thereby'reversing the rotation ofthe tap to move it fromthe work piece. The reversing rotation is faster than the clockwise rotation usedin. cutting' th'e thread because; of .thesmaller pulley 29'. :The'tapmay be tion that I have provided a novel machine for forming screw threads in a work piece which has a low inertia constant to prevent tool breakage, which is extremely sensitive to the application of pressure, which has a minimum of tap and die breakage, which eliminates all violent impacts from the. use of lugs and stops, and one which may be operated by an unskilled operator to form perfect threads.

Various changes may be made in the specific embodiment of my invention without departing from the spirit thereof or from the scope of the appended claim.

What I claim is:

In a machine tool, a support frame, a rotatable hollow spindle mounted on said frame and supported for axial movement adjacent each end thereof by spaced bearings, spaced disks rotatably mounted on said frame between said spaced bearings, a double faced clutch member disposed between said disks and adapted to selectively frictionally engage one of said disks, said clutch member being fixed to said hollow spindle and concentric therewith, means to bias said clutch member to a neutral position between said disks, means to rotate said disks in opposite directions, an axially aligned non-rotatable spindle attached to one end or said rotatable spindle, guide means 6 fixed to said frame for said non-rotatable spindle, said guide means spaced from said spaced bearings, said non-rotatable spindle extending through said guide means. a rotatable shaft concentric with and slidable and rotatably associated with said rotatable spindle and extending through sadi non-rotatable spindle, a telescnping sleeve slidably mounted in said non-rotatable spindle and forming a bearing for said rotatable shaft, means to attach a tool to said rotatable shaft, and means on said non-rotatable spindle.

to move said sleeve and said spindle in opposite. directions whereby said clutch is brought into engagement with one of said disks when a tool in said holding means contacts a fixed object.

STEVE CSENCSICS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 610,208 Tuttle Sept. 6, 1898 832,221 Tuttle Oct. 2, 1906 1,244,084 Shafer Oct. 23, 1917 1,459,981 McClellan June 26, 1923 

